Difference: SansaE200FirmwarePartition (r6 vs. r5)

SanDisk Sansa E200 Firmware Partition

Description

The SanDiskSansa e200 series has a 20MB hidden firmware partition. It holds both the bootloader and main firmware. This partition is either not present or hidden by e200r firmwares.

The partition is 20MB and is at the end of the disk. It doesn't have any partition table, but has files at specific address locations inside it. Each file has a 512B (1 sector) header which has a 4 character string describing its contents, followed by a 32-bit little endian number indicating the length of the file in bytes. There is then a 32 bit number with an unknown purpose.

Structure

Addresses are relative to the start of the partition. The partition is divided up into 3 block. The first block is 512KB for the bootloader. The last 5MB of the partition is for the ppfn (image?) data. The remaining space in between is used for the main firmware.

Address	Description
0x0	Bootloader header - PPBL followed by the bootloader length, followed by 0x10000
0x200	Bootloader
0x80000	Main firmware header - PPMI followed by firmware length, followed by 0x20000
0x80200	Main firmware in mi4 format
0x780000	NVPARAMS
0x780200	PPPS Non-volatile parameters - used by the OF to save data (eg. current track, database status, etc.) through a power cycle. There appears to be a header here too
0x7810e1	If this is set to 1, the database is rebuilt on next reboot
0x800000	Unknown data of length 0x200
0xefe400	PPID followed by length (0x10), followed by 0x40000
0xefe600	ppid data. Unknown purpose. Reads `DF 83 75 C6 F6 FC 1A 44 84 66 45 99 6C E1 DC 70` on Sansa e280
0xf00000	PPFN followed by length followed by 0x30000
0xf00000	ppfn data. Possibly images or animation used by the bootloader

View topic | View difference side by side | History: r7 < r6 < r5 < r4 | More topic actions

r7 - 22 Oct 2007 - 17:22:20 - BertrikSikken

Revision r6 - 21 Oct 2007 - 19:54 - JackSuter
Revision r5 - 20 Oct 2007 - 15:02 - BarryWardell